Question about fittingsand hardware

[E30_S50]

would anybody be able to suggest to me a good source of info explaining the different types of high pressure fittings/systems? From what I understand there is scba, scuba, din3000.

My problem is that I believe I have a mix of 2 kinds of pseudo compatible fittings. Some of the threaded connections have flat interface while the ones included on my big cf tank hose have a convex/concave interface. What system is the convex interface called? Here is a photo of the threaded end on the hoses female quick disconnect fitting. It is damaged and and I need to get a replacement before I can fill my airgun . It goes to an Apeks valve on my tank

do they sell an adapter between the concave threaded fitting and the flat nosed threaded fittings?

 

[E30_S50]

Here is another photo showing the two different systems of fittings I have. I am essentially looking for a female quick disconnect fitting to attach to the end of the hose pictured. The one that came on my hose seems to have malfunctioned and is jammed (a male piece is jammed inside and won't release...it also slowly leaks under pressure)